Animator Play Sub State machine

I have to make a simple animation for player falling left or right.
So I have a sub-state machine called Fall which will play the desired animation based on the Direction.
Now if I have to play a particular state I just usually call animator.Play (stateName) but how do I just transition to a sub-state machine and let it decide which animation to play?

Unity forces us to use visual-scripting. You will have to setup transitions in the animator window of a given AnimatorController, - an element which sits on Animator component of your creature.

After you’ve setup the transitions, make them dependent on parameters in that animator

From code, you can fire a transition, by making its parameter comply with the transition’s requirement.

myAnimatorReference.SetBool("nameOfBoolParameter", false); or float, int etc.

This could be a transition to your stateMachine, if you’ve set it up that way.

You can stick a stateMachineBehavior on your StateMachine, to let if further decide which sub-state to play